216 THE FAIRY-LAND OF SCIENCE. 
The reason of this is that grasses, sedges, rushes 
nut-trees, willows, and the others we have mentioned, 
have all of them a great deal of pollen-dust, and as 
the wind blows them to and fro, it wafts the dust from 
one flower to another, and so these plants do not want 
the insects, and it is not worth their while to give out 
honey, or to have gaudy or sweet-scented flowers to 
attract them. 
But wherever you see bright or conspicuous flowers 
you may be quite sure that the plants want the bees 
or some other winged insect to come and carry their 
pollen for them. Snowdrops hanging their white 
heads among their green leaves, crocuses with their 
violet and yellow flowers, the gaudy poppy, the large- 
flowered hollyhock or the sunflower, the flaunting 
dandelion, the pretty pink willow-herb, the clustered 
blossoms of the mustard and turnip flowers, the 
bright blue forget-me-not and the delicate little 
yellow trefoil, all these are visited by insects, which 
easily catch sight of them as they pass by and hasten 
to sip their honey. 
Sir John Lubbock has shown that bees are not only 
attracted by bright colours, but that they even know 
one colour from another. He put some honey on 
slips of glass with coloured papers under them, and 
when he had accustomed the bees to find the honey 
always on the blue glass, he washed this glass clean, 
and put the honey on the red glass instead. Now if 
the bees had followed only the smell of the honey, 
they would have flown to the red glass, but they did 
not. They went first to the blue glass, expecting to 
